Dynamotor



March 15, 1955 Filed Nov. 18, 1952 H. D. BRAlLsl-ORD 2,704,334

DYNAMoToR 2 Sheets-Sheet l Fgg; l@ rml@ 56 j@ @mfgw March l5, 1955 H, D,BRAlLsFORD 2,704,334

DYNAMOTOR Filed Nov. 18, 1952 2 Sheets-Sheet 2 ILC'.\ K

A1%.@ Sja @L IAAAA l United States Patent O DYNAMOTOR Harrison D.Brailsford, Rye, N. Y.

Application November 18, 1952, Serial No. 321,131

9 Claims. (Cl. 310-68) The present invention relates to dynamotors andparticularly to a device which is small and compact and which is capableof generating alternating current of up to approximately 1500 volts froman input operating at 4.5 volts at 30 milliamperes. In one form of theinvenvention, a motor portion of the device is a structure similar tothat shown in my Patent No. 2,457,637, issued December 2S, 1948.

in a modified form of the invention the motor rotor, instead ofrotating, oscillates and the controlling contacts are arranged toproduce this type of operation. The output is, as in the first formmentioned, a high voltage A. C. output.

lt is an object of my invention to provide a dynamotor which isextremely small and compact and which is capable of an output voltagemany times that of the input.

It is another object of my invention to provide such a device utilizingthe motor structure of my prior patent above-identified.

It is another object ofthe invention to provide a dynamotor having anoscillating rotor member and which generates an alternating current ofhigh voltage.

Other objects and features of the invention will be apparent when thefollowing description is considered in connection with the annexeddrawings, in which,

Figure l is a top plan view of the dynamotor of my invention;

Figure 2 is a side elevation of the motor structure of Figure 1;

Figure 3 is a top plan View of the field pieces and rotor with the rotorsupports removed. In this figure the motor circuit is shown indiagrammatic form;

Figure 4 is a top plan view of a dynamotor similar to that of Figures 1through 3, the device being modified to provide an oscillating ratherthan a rotating rotor; and

Figure 5 is a top plan view of a device of the same type as that shownin Figure 4 but slightly modified in that the rotor is of rectangularshape and extends between the pole pieces.

Referring now to the drawings, there is shown therein a laminated fieldcore having the two pole pieces 11 and 12 and a winding 13 which windinghas a common center tap thus providing effectively two field windingsdesignated 14 and 1S. A battery 17 (see Figure 3) is connected to thecenter tap and the other ends of the coils 14 and 15 are connected bysuitable conductors to the flexible contact members and 21. Members 20and 21 are suitably supported intermediate upper and lower frame members22 and 23 on aninsulating support 19 as shown in Figures l and 2.

A rotor 26 of disk shape is mounted on a shaft 28 which is journalled atits upper and lower ends in the corresponding frame members 22 and 23.

Shaft 28 is provided with a cam 29 which is located between the free endportions of the contacts 20 and 21. Cooperating with the contacts 20 and21 are fixed contacts 20a and 21./z respectively, the arrangement beingsuch that the opening and closing of the contact pairs is controlled bythe cam 29. The arcuate extent of the cam 29 is approximately 260 withthe result that during each complete rotation of the shaft 2S thecontact pair 21, 21a is closed for 100 and open for 260, the contactpair 20, 20a is closed for 100 and open for 260, and during two periodsof 80 each, both contact pairs are open.

The rotor 26 is formed of highly magnetizable material such as Alnicoand is permanently magnetized in a diametrical band to provide magneticpoles at the armature periphery, these poles being marked N and S inFigure 3. The magnetic effect of the poles is strongest at the twoindicated pole portions, but the magnetism spreads out with decreasingstrength from each polar region toward areas indicated generally, butnot precisely, by the boundary lines N and S. Within the boundary linesN and S the armature is not magnetized or at least not appreciablymagnetized.

The field poles 11 and 12 are provided with pole faces 11a and 12arespectively which are eccentric with respect to the axis of rotation ofrotor 26. Thus the pole faces are spaced from the armature periphery bya gap which decreases in a counterclockwise direction as viewed inFigure 3.

Referring to Figure 3, the magnetic poles of the armature are shown in aposition corresponding to the shortest possible magnetic path betweendiametrical portions 11a and 12a of the pole faces 11 and 12. The cam 29is in contact with the contact member 21 and out of contact with 20,that is, contacts 20, 20a are closed and 21, 21a open. Upon closing ofthe circuit through the field winding, as for example by means of switch32, the coil 15 will be energized. This coil is so wound and the currentso poled that the field pole 11 will be north and the field pole 12 willbe south. The north field pole 11 will, at its upper portion as viewedin Figure 3, repel the north pole of the armature in a counterclockwisedirection. The south field pole 12 at its lower portion will similarlyrepel the south pole of the armature. Concurrently with the repellingaction of each field pole on the armature poles of like polarity, theupper portion of the south field pole 12 will attract the north pole ofthe armature while the lower' portion of the north field pole 11 willattract the south tieid pole of the armature, these forces acting in adirection to produce counterclockwise rotation of the rotor.

When the cam 29 has moved through an arc of approximately 50 from theposition shown in Figure 3, the field circuit for winding 14 is brokenby separation of the contacts 20, 20a and the field poles thereuponbecome nonmagnetic. However, the permanent magnetic poles of thearmature, due to the attraction of the same to the faces of the fieldpoles, continue to exert rotative force on the rotor by reason of thedecreasing air gap between the permanent magnet poles of the rotor andthe faces of the field pole.

The rotor will, of course, tend to come to rest in a positionapproximately 180 from the position indicated in Figure 3. However,prior to this time and when the rotor has advanced through approximately130 of arc from the position shown in Figure 3 contacts 21, 21a willhave closed thereby effecting energization of coil 15. This results inenergization of the field winding and magnetic reenergization of thefield poles but with the polarity reversed with respect to that of theprior half-cycle. Field pole 11 will now be a south pole and field pole12 a north pole and they will cooperate as described above each to repelthe rotor pole of like polarity.

After a further rotation of approximately the field poles will again bede-energized by movement of the cam 29 out of contact with both contacts20 and 21. During the subsequent 80 rotative force is applied by theattractive force existing between the permanent rotor poles and thenon-magnetized eld pole faces through the gap that constantly decreasesin the direction of rotor rotation. When the rotor arrives at theposition shown in 'Figure 3 the cam 29 will again permit closure ofcontacts 20, 20a and the cycle will repeat.

A winding 50 is wound on the field structure comprising the pole pieces11 and 12, this field winding being placed on the same core portion 51on which windings 14 and 15 are placed. As will be` clear the magneticflux threading the winding 50 will be the same as that which threads thewindings 14 and 15.

At the instant that switch 32 is closed and assuming the startingconditions above described in connection with Figure 3, current flowsthrough the right half 14 of the motor field winding 13. The winding 14is so proportioned that the fiux produced in the core 51 is equal andandasse opposite to the fiux produced in that core by the permanentlymagnetized rotor, the net flux in the core 51 being zero.

As a result of the repulsion action above described, the motor revolvesin a counterclockwise direction. As soon as the rotor has reached avvertical position with respect to its axis of magnetization, the fluxthreading the field as a result of the permanent magnetization of therotor is modified and a portion thereof threads the core in a directionopposite to that of the remainder. As rotation continues all of the fluxdue to the permanently magnetized rotor threads the core in thedirection opposite to that at starting. Since the winding 14 remainsenergized there will now be a fiux threading the windings 14 and 5t)which is twice that due to the winding 14 or to the permanentmagnetization of the rotor 26 alone.

Shortly thereafter the contacts 21, 21a open and the electromagneticfield consequently collapses. There is thus the additive effect ofreversal of the fiux threading winding 14 resulting from the permanentmagnetization of the rotor and collapse of the electrically induced fluxin that same core 51. This results in a sharp peak in the wave form ofthe alternating flux, the sequence being repeated during following halfrevolutions by operation of the contacts 20, a and 21, 21a alternately.

The winding 50, being threaded by the alternating flux mentioned, hasgenerated therein a corresponding voltage. This voltage may be utilizedas an alternating current voltage or may be rectified to produce a D. C.output by means of the simple circuit shown and comprising half waverectifiers 52 and S3 together with the condensers 54 and 55. Therectified current appears at terminals 56.

This arrangement generates voltages substantially higher than arepossible from rotating mechanisms of comparable size and conventionaldesign. A typical unit of the type described weighs less than sixounces. It operates on an input voltage of 41/2 volts at 30 milliamperesand delivers up to 1500 volts D. C.

Referring now to Figure 4, there is shown therein a device generallysirnilar to that of Figures 1 and 3 and therefore having partsdesignated by the same reference characters as are applied to thosefigures. In this arrangement the permanent magnet member 26 is generallyrectangular in shape rather than round as in the foregoing figures andis mounted on a shaft 28 which may be in turn mounted in the same manneras in the arrangement first described. A single set of contacts 60, 61is provided which contacts are normally closed but may be caused to openby means of the member 62 fixed to the shaft 28. In place of the centertapped winding 13 of Figures l through 3 the contacts 60 and 61 are inthis instance connected through the battery 17 and switch 32 to awinding 63. A second winding is connected through the rectifier 64 tothe output terminals 65, a condenser 66 being shunted across theterminals as clearly shown in Figure 4.

At rest fiux from the permanently magnetized rotor 26 passes through thepole piece 11, through core 51 and through pole piece 12 to the oppositepole of the rotor. When the switch 32 is closed current from the battery17 passes through the operating winding 63 in a direction causing theupper pole face 11a to become a north pole and lower pole face 12a tobecome a south pole which is the reverse of the polarity of the upperand lower ends of the rotor 26 respectively. As in the form firstdescribed the winding here designated 63 is so proportioned that theflux produced in the core 51 is equal and opposite to the fiux producedin that core by the permanently magnetized rotor 26 and consequently thenet fiux in the core is zero.

However, as a result of the like poles being adjacent Vthe rotor tendsto move in a counterclockwise direction.

When the rotor 26 has turned far enough for its flux to add to theelectromagnet field, that is, when the rotor has turned far enough sothat the fiux path is through the upper portion of pole face 12a andlower portion of pole face 12a, the contact member 62 raises the Contactspring 60 thus causing contacts and 61 to open interrupting the currentto the winding 62 and causing a collapse of the electromagnetic field.The rotor then returns to its original position due to the attraction ofits field on the pole faces 11a and 12a. This collapse of theelectromagnetic .field together with the mechanical reversal of themagnetic field set up by the rotor causes an inductive peak whichgenerates a high voltage in the generating winding 50. This highVvoltage current may be rectified by the half-wave rectifier 64cooperating with the condenser 66 in a well-known manner or the fullwave rectifying circuit shown in Figure 3 may be utilized.

In Figure 5 there is shown a slight modification of the Figure 4arrangement wherein the shape of the rotor and the pole pieces ischanged since in the Figure 4 form the rotor simply oscillates andtherefore it is unnecessary to have it mounted for continuous rotation.Therefore in the Figure 5 form the rotor ends extend between the polefaces 11a, 12a. In this form of the invention, of course, the samecontact operator 62 is employed as was employed in the Figure 4 form andthe adjustment is such that the contacts 66 and 61 open before the endsof rotor 26 can come into contact with the pole faces 11a and 12a. Infact, the contacts 60 and 61 open just prior to the time when the rotor26 would arrive at the vertical position as shown in Figure 5 whichassures the return of the rotor to the position indicated. Were therotor to pass beyond a position slightly inclined clockwise from thevertical, it might then move against the pole faces 12a and 11a andrender the device thereafter operative.

Considerable modification of the above devices may be made. For example,the shape of the field may be altered for convenience in manufacture,the contact design may be changed, etc. In addition, it is entirelypossible to eliminate the second winding 50 and take alternating currentdirectly from the outer terminals of the center tapped coil 13, althoughit is generally preferable to separate the high and low voltage circuitsin the manner shown in the drawing.

While I have described preferred embodiments of my invention, it will beunderstood that many modifications may be made within the scope thereof.Consequently, l wish to be limited not by the foregoing description, butsolely by the claims granted to me.

What is claimed is:

l. A dynamotor Acomprising in combination a pair of field poles having acore portion integral therewith, a winding on said core forelectromagnetically energizing said field poles, a rotor memberpositioned between the field poles and within the electromagnetic field,said rotor being of magnetizable material and being magnetized to formpermanent north and south poles at diametrically opposite points of itsperiphery, contact means operable by the rotor for supplying energizingcurrent to the field winding, said energizing current and winding beingproportioned so that the magnetic flux in said core portion caused bycurrent flow in said winding is equal to the fiux in said core portionresulting from said permanently magnetized rotor, said contact meansbeing positioned relative to said rotor so that said-electromagneticfield and permanently magnetic field together and said permanent magnetfield alone are alternately effective to produce movement of said rotor,the fiux in the said core varying with each rotor movement from aminimum to a maximum value, and means for applying a current derivedfrom said build up and decay of fiux to an external circuit.

2. A dynamotor comprising, in combination, a pair of field poles havinga core portion integral therewith, a winding on said core forelectromagnetically energizing said field poles, a rotor memberpositioned between the field poles and within the electromagnetic field,said rotor being of magnetizable material and being magnetized to formpermanent north and south poles at diametrically opposite points of itsperiphery, Contact means operable by the rotor for supplying energizingcurrent to the field Winding, said energizing current and winding beingproportioned so that the magnetic flux in said core portion caused bycurrent fiow in said winding is equal to the flux in said core portionresulting from said permamently magnetized rotor, said contact meansbeing positioned relative to said rotor so that said electromagneticfield and permanently magnetic field together and said permanentlymagnetic field alone are alternately effective to produce movement ofsaid rotor, the linx in the said core varying with each rotor movementfrom a minimum to a maximum value, and a second winding on said core thebuilt up and decay of flux in said core generating an electrical currentin said winding.

3. A dynamotor comprising an electromagnetic field Ahaving a core, apairof field poles and a pair of windings alternately energizable foreffecting reversal of polarity of said field poles, at rotor positionedbetween said field poles and within the magnetic field thereof, saidrotor being of disk form and being permanently magnetized along adiameter thereof to provide permanent north and south poles, said iieldpoles having arcuate pole faces positioned adjacent the periphery of therotor and spaced therefrom to provide air gaps which decrease in widthin the direction of rotation of the rotor, means operable by the rotorfor supplying energizing current to the winding in opposite directionsfor effecting reversal of polarity of said field poles during portionsof each cycle of rotation of the rotor for producing both attractive andrepelling forces which act on said rotor during each energization of thewinding to produce rotation of the rotor, the current through saidWinding and the winding itself being so proportioned that the magneticux in said core portion caused by said electric current is equal to theflux in said core portion resulting from said permanently magnetizedrotor whereby as the rotor rotates the flux in said core portion variesfrom substantially zero to a maximum value, and means for applying acurrent derived from said flux variation in said core to an externalcircuit.

4. A dynamotor comprising an electromagnetic field having a coreportion, a pair of ield poles and a pair of windings alternatelyenergizable for effecting reversal of polarity of said eld poles, arotor positioned between said field poles and within the magnetic fieldthereof, said rotor being of disk form and being permanently magnetizedalong a diameter thereof to provide permanent north and south poles,said field poles having arcuate pole faces positioned adjacent theperiphery of the rotor and spaced therefrom to provide air gaps whichdecrease in width in the direction of rotation of the rotor, meansoperable by the rotor for supplying energizing current to the winding inopposite directions for effecting reversal of polarity of said fieldpoles during portions of each cycle of rotation of the rotor forproduring both attractive and repelling forces which act on said rotorduring each energization of the winding tol produce rotation of therotor, the current through said winding and the winding itself being soproportioned that the magnetic iux in said core portion caused by saidelectric current is equal to the ilux in said core portion resultingfrom said permanently magnetized rotor whereby as the rotor rotates theflux in said core portion varies from substantially zero to a maximumvalue, and a second winding on said core the build up and decay of fluxin said core generating an electrical current in said winding.

5. A dynamotor comprising a core portion having a pair of eld polesintegral therewith, a winding on said core for electromagneticallyenergizing said field poles, a rotor member positioned between the eldpoles and within the electromagnetic field, said rotor member beingpermanently magnetized to form permanent north and south poles adjacentthe ends thereof, contact means operated by the rotor for alternatelymaking and breaking a supply circuit to said field winding, said rotorbeing urged in one direction when said eld winding is energized, andbeing returned to a normal position on de-energization of said eldwinding, said eld winding being so proportioned with respect to thecurrent supplied thereto that the flux resulting in said core fromelectrical energization of said winding is substantially equal to theflux flowing in said core due to said permanent magnetization of saidrotor, the flux in said core varying with each oscillatory cycle of saidrotor from a minimum to a maximum value, and means for applying acurrent derived from said varying iiux to an external circuit.

6. A dynamotor comprising a core portion having a pair of eld polesintegral therewith, a winding on said core for electromagneticallyenergizing said eld poles, a rotor member positioned between the fieldpoles and within the electromagnetic eld, said rotor member beingpermanently magnetized to form permanent north and south poles adjacentthe ends thereof, contact means operated by the rotor for alternatelymaking and breaking a supply circuit to said field winding, said rotorbeing urged in one direction when said iield winding is energized, andbeing returned to a normal position on deenergization of said fieldwinding, said eld winding being so proportioned with respect to thecurrent supplied thereto that the iiux resulting in said core fromelectrical energization of said winding is substantially equal to theilux flowing in said core due to said permanent magnetization of saidrotor, the flux in said core varying with each oscillatory cycle of saidrotor from a minimum to a maximum value, and a second winding on saidcore the build up and decay of flux generating an electrical current insaid winding.

7. A dynamotor comprising, in combination, an electromagnetic iieldhaving a pair of field poles and a winding alternately energizable andde-energizable for polarizing said iield poles, a rotor positionedbetween said field poles and Within the magnetic iield thereof, saidrotor being of disk form and being permanently magnetized along adiameter thereof to provide permanent north and south poles, said iieldpoles having arcuate pole faces positioned adjacent the periphery of therotor and spaced therefrom to provide air gaps which decrease in widthin the direction in which the rotor moves when said iield poles areenergized, means operable by the rotor for supplying energizing currentto the winding for producing repelling forces which act on said rotor toproduce movement in said one direction, said permanent magnetization ofsaid rotor producing a restoring force to move the rotor in the oppositedirection, the magnetic iiux in the core portion of the electromagneticfield varying as said ield winding is energized and de-energized wherebyas the rotor oscillates the ux in said core portion varies from aminimum to a maximum value, and means for applying the current derivedfrom said flux Variation in said core to an external circuit.

8. A dynamotor comprising, in combination, an electromagnetic fieldhaving a pair of field poles and a winding alternately energizable andde-energizable foi' polarizing said iield poles, a rotor positionedbetween said field poles and within the magnetic eld thereof, said rotorbeing of disk form and being permanently magnetized along a diameterthereof to provide permanent north and south poles, said eld poleshaving arcuate pole faces positioned adjacent the periphery of the rotorand spaced therefrom to provide air gaps which decrease in width in thedirection in which the rotor moves when said eld poles are energized,means operable by the rotor for supplying energizing current to thewinding for producing repelling forces which act on said rotor toproduce movement in said one direction, said permanent magnetization ofsaid rotor producing a restoring force to move the rotor in the oppositedirection, the magnetic ux in the core portion of the electromagneticeld varying as said field winding is energized and de-energized wherebyas the rotor oscillates the ux in said core portion varies from aminimum to a maximum value, and a second winding on said core portionthe build up and decay of ux in said core portion generating anelectrical current at high voltage in said winding.

9. A dynamotor comprising an electromagnetic field having a coreportion, a winding thereon and a pair of eld poles, said field polesbeing alternately energizable f or effecting reversal of polaritythereon, a rotor positioned between said field poles and within themagnetic field thereof, said rotor comprising a permanently magnetizedbar mounted for oscillatory movement, means operable by the rotor formaking and breaking a circuit to said field winding for producingattractive and repelling forces ac ting on said rotor during eachenergization of the winding to produce movement away from a normal restposition, said permanently magnetized rotor providing a restoring forcefor restoring the rotor to the normal rest position upon thede-energization of said eld windin g, .said flux resulting fromenergization of said field winding aswell as from permanentmagnetization of said rotor passing through said core whereby as therotor oscillates the flux in said core varies from a minimum to amaximum value, and means for applying a current derived from said fluxvariation in said core to an external circuit, said current being at avoltage many times that of the direct current input to said energizingwinding.

References Cited in the le of this patent UNITED STATES PATENTS2,278,061 Dalkowitz Mai'. 31, 1942 2,457,637 Brailsford Dec. 28, 1948

